Force-feed lubricator.



H. LE R. DAVIS. FORGE FEED LUBRIGATOR. APPLIGATION FILED JAN. 11, 1910.

Patented May 24, 1910.

ville/way HARRY LE ROY DAVIS, OF SENECA- FALLS, NEW YORK.

FORCE-FEED LUBBICATOB.

Specification of Letters Patent.

Patented May 24, 1910.

Application filed January 11, 1910. Serial No. 587,44;1.

I To all it may cmwem:

the State of New York, have invented new and useful Improvements in Force-Feed Lubricators, of which the following, taken in connection with the accompanying drawings, is a full, clear, and exact description.

This invention relates to certain improvements in force feed lubricators of the hand operated type commonly known in the trade as grease guns and comprising a cylinder for the lubricant, a piston movable in the cylinder and manually operated means for advancing the piston, step by step, to expel the lubricant therefrom through the discharge nozzle and into the bearings of automobiles and other machines where gravity feed is impracticable or unreliable.

I am aware that it is not broadly new to provide manually operating means for advancing a piston, step by step, in a cylinder for injecting a lubricant therefrom, but in all of those with which I am familiar the pawl action for effecting such step by step movement is unreliable for any great length of time or period of use and the main object of my present invention is to render this step by step movement more positive and enduring and less'liable to get out of repair in the hands of inexperienced operators. To this end the piston rod is provided with a toothed rack, the teeth of which are adapted to be successively engaged by a lever operated pawl for advancing the piston step by step, one or more teeth at a time, as the lever is operated.

Another object is to retract the lever and to force the pawl into engagement with the teeth of the rack by means'of a single spring.

A further object is to provide a simple means for disenga ing the apawl from the teeth of the rack w en the lever is retracted by the spring, so as to leave the piston and nston rod free to be operated by hand 1ndependently ofz-the lever and pawl.

Other objects and uses relating to specific parts of the device will be brought out in the following description.

In the drawings: Figure 1 is a longitudinal vertical sectional view partly in elevation of a force feed lubricating device embodying the various features of my invention, the lever and pawl being shown in their normal positions. Fig. 2 is an enlarged elevation of the upper portion of the device showing parwhich it projects.

side thereof, just above the head 3- ticularly the piston operating mechanism in its operative position for advancing the pis ton. Fig. 3 is a transverse sectional View taken on line 3-3, Fig. 1. Fig. 4 is an elevation of the upper portion of a grease gun showing a slightly modified form of a piston operating mechanism in which the retracting sprin for the lever is interposed between the heel of the pawl and head of the cylinder, but located so as to force the pawl into operative engagement with the teeth of the rack when the lever is rocked to its operative position.

The grease, or other lubricant, is placed within one end of a suitable cylinder lsuch end being provided with a discharge nozzle -2 screwed thereon and adapted to be removed to permit the cylinder to be easily filled with such lubricant. The opposite end of the cylinder is closed by a suitable cap 3 having a central opening at which, in this instance, is angular in cross section.

Movable in the cylinder is a piston 5 having an outwardly projecting stem -(S- which is also angular in cross section to slide easily through the opening at" through The piston rod 6- is provided on one side with a toothed rack T extending the greater portion of its length the outer end of the piston rod being provided with a handle -8- by which the rod and piston may be operated back and forth. A hand lever -8- of the bell crank type is pivoted at 9- to an upwardly projecting arm 10 on the head -3 one arm of said lever constituting a handle running lengthwise of'the piston rod some distance above the head -3. The other arm of the lever is bifurcated or slotted to receive the upwardly projecting rod -6-- which extends therethrough, that is, the short arm of the lever'which is pivotally supported at one side of the piston rod extends to the opposite with suiiicient clearance to allow its vertical play.

A pawl 11- is pivoted at its lower end at -12 to the short arm of the lever 8 adjacent to the toothed rack 7- and extends upwardly from its pivot, the upper end being provided with a tooth 12 adapted to successively engage the teeth of the rack as the handle of the lever --8- is pressed inwardly by hand toward the piston rod, thereby rocking the short arm of the lever downwardly to advance the piston. r

. manner as to force said with the teeth of the rack 1, 2 and 3.

ings, that'the pawl and ran spring -l3 has one end connected to the upper end of the pawl 11 and itsother end connected to a guide arm 14 projecting laterally from an upright bracket -l5 rising from the head -3, said guide arm being provided with a vertical guide opening l6- through which the piston rod -6 extends. The spring 13 is connected to the awl 11 at a point to one side of a stralght line drawn between the pivot -12 and point of connection of said spring with the arm 14 in such pawl into engagement' with the teeth of the rack 7 when the lever -8- is forced to its operative position, as shown in Fig. 2.

Rigidly secured to the bracket l 5- is a laterally projecting arm -17- having its free end provided with a downwardly inclined cam or beveled face l8- which lies in the path of and is adapted to be engaged by a pin or stud -19 on one side of the upper end of the pawl -11, so

In Fig. 4 have shown a slightly modified form of operating mechanism for the piston in which the pawl is provided with a laterally projecting heel 20 at one side of its pivot l2- and adapted to be engaged by one end of a com resslon spring 21 having its other en resting upon the upper end of the head 3, said spring serving the same purpose as the sipring 13 to retract the lever 8 an also to force the pawl -11 into engagement 7- when the lever 8 is pressed inwardly by hand against the action of its retracting spring,

thereby drawing the pin 19 of the pawl 11 out of engagement with the cam tooth 18, otherwise the mechanism is substantially the same as that shown in t will be seen upon reference to the foregoing description'and=--aotiim anying drawoperating in the manner described afford a positive and durable means for advancing the piston, step by step, as the lever -8 is operated by hand and retracted by the spring 13-- or 21 and that cam tooth -l8 coacting with the shoulder or pin 19 also affords a positive means for disen from the piston rod when t e lever is in its aging the pawlnormal position leaving the piston and its iston rod free to be moved back and forth y means of a handle 8.

The piston rod 6 and guide 0 ening 4- 1n the head 3 are pre erably square in cross section and serve to hold the rod against turning with its toothed side adjacent the pawl -11-, the gulde openings 4 and -16 being of sufficient size to permit free movement of the plston rod therein without excessive frictlon.

The bracket 15 is provided near the head or cap 3 with a laterally project ing thumb piece -23- adapted to be en gaged by the hand when operating the lever 8 to enable the operator to obtain a better grip on the device, the bracket -15 also serving as a portion of the handle for holding the device in operative position.

What I claim is:

.1. A force feed device for lubricants, comprising a cylinder having a discharge nozzle on one end and a gulde opening in its opposite end, a iston movable in the cylinder and roviriiad with a piston rod hav ing a toot ed rack on one side running lengthwise. thereof, a lever operatively mounted on the cylinder, a pawl on the lever adapted to en age said rack and advance the piston as the ever is operated, and a spring operatively connected to the pawl to force the same into engagement with the rack when the lever is operated, said sfpring also operating through the medium 0 to retract the lever.

2. A force feed lubricating device, comprising acylihder havinganozzle on one end and a guide opening in its opposite end, a piston movable in the cylinder and provided with a rod extending said openings, a toothed rack on the rod, a bell crank lever operatively mounted on the cylinder having a longarm and a short arm the long arm constituting a handle and the short arm extending laterally beyond the rod and provided wlth an opening for receiving said rod, a pawl pivoted to the short arm 0 the lever and spring pressed against the rack when the lever 18 operated, said spring. operating to retract the lever, a 'pin projecting laterally from one side of the pawl, abracket on the cylinder, and a cam .tooth on the bracket having its cam face in the 1path of movement of the pin on the paw for engaging said pin and withdrawing the pawl from engagement with the rack when the lever is retracter. to its normal position. v I

In witness whereof I have nereunto set my hand on this 8th day of J anuvry 1910.

HARRY LE ROY DAVIS.

. Witnesses:

JOHN C. DAVIS, E. M. PERRY.

the pawl 

